Add Util.toHexString

PiperOrigin-RevId: 295539969

library/common/src/main/java/com/google/android/exoplayer2/util/Util.java

@@ -1256,6 +1256,22 @@ public final class Util {
   }
   }
 
 
   /**
   /**
+   * Returns a string containing a lower-case hex representation of the bytes provided.
+   *
+   * @param bytes The byte data to convert to hex.
+   * @return A String containing the hex representation of {@code bytes}.
+   */
+  public static String toHexString(byte[] bytes) {
+    StringBuilder result = new StringBuilder(bytes.length * 2);
+    for (int i = 0; i < bytes.length; i++) {
+      result
+          .append(Character.forDigit((bytes[i] >> 4) & 0xF, 16))
+          .append(Character.forDigit(bytes[i] & 0xF, 16));
+    }
+    return result.toString();
+  }
+
+  /**
    * Returns a string with comma delimited simple names of each object's class.
    * Returns a string with comma delimited simple names of each object's class.
    *
    *
    * @param objects The objects whose simple class names should be comma delimited and returned.
    * @param objects The objects whose simple class names should be comma delimited and returned.

library/common/src/test/java/com/google/android/exoplayer2/util/UtilTest.java

@@ -706,6 +706,13 @@ public class UtilTest {
   }
   }
 
 
   @Test
   @Test
+  public void testToHexString() {
+    byte[] bytes = TestUtil.createByteArray(0x12, 0xFC, 0x06);
+
+    assertThat(Util.toHexString(bytes)).isEqualTo("12fc06");
+  }
+
+  @Test
   public void testGetCodecsOfType() {
   public void testGetCodecsOfType() {
     assertThat(getCodecsOfType(null, C.TRACK_TYPE_VIDEO)).isNull();
     assertThat(getCodecsOfType(null, C.TRACK_TYPE_VIDEO)).isNull();
     assertThat(getCodecsOfType("avc1.64001e,vp9.63.1", C.TRACK_TYPE_AUDIO)).isNull();
     assertThat(getCodecsOfType("avc1.64001e,vp9.63.1", C.TRACK_TYPE_AUDIO)).isNull();